Your Guide to Placenta Positions!

Last Updated: January 30, 2024
Liesel Teen, RN-BSN

By Liesel Teen

BSN, RN, Practicing Labor and Delivery Nurse

This article may contain affiliate links. This means that if you make a purchase through these links, we may earn a small commission at no additional cost to you. Learn more about affiliate links.

Curious about where your placenta is? Wondering what the deal is with different placenta positions? You are in the right place!

I don’t know about you, but the placenta fascinates me! Just think about everything it does. Not only does it provide oxygen and nutrients to help your baby grow, but it also eliminates waste. 

For all intents and purposes, it is your growing baby’s lifeline.

This article is jam packed with tons of info and the only guide to placenta positions you need to read during pregnancy. 

I’m going to cover it all, mama, so let’s get going!

Follow @mommy.labornurse on Instagram to join our community of over 640k for education, tips, and solidarity on all things pregnancy, birth, and postpartum!

What is the placenta?

I realize this might be review for some of you, but the placenta is just so incredible that I want to make sure I cover all my bases. 

So, what is the placenta? The placenta is actually an organ, believe it or not, and a very important organ at that! 

It supports baby’s development in utero by: 

  • Providing nutrients
  • Eliminating fetal waste
  • Enabling gas exchange via maternal supply 

Pancake in shape, the placenta is attached to the uterine wall on one side and to baby’s umbilical cord on the other end. 

The placenta holds approximately 150 mL of maternal blood that is renewed 3-4 times per minute…I can’t be the only one mind blown by that!

What does the placenta do?

The placenta plays a very important role in pregnancy. Like I said, it provides nutrients, eliminates waste, and enables gas exchange for your developing baby. 

But, it’s one of the only organs in your body that’s “disposable”, meaning once your body is done using it, it expels it – hello third stage of labor!  

The placenta has two sides, maternal and fetal. The maternal side (which is dark red in color) is attached to the uterine wall. The fetal side (which is shiny in appearance) is attached to baby’s umbilical cord. 

So yeah, I would say the role of your placenta during pregnancy is a pretty darn important one!

When does the placenta form?

The placenta begins forming soon after a fertilized egg implants in the uterus. Almost immediately the placenta will start secreting the hormone hCG, which is responsible for establishing and maintaining early pregnancy. 

Even though the placenta begins to form very early on, it takes until weeks 10-12 for it to be fully functioning and take over providing for your baby. 

This explains why the first trimester can be so exhausting and why a lot of mamas experience such significant morning sickness in the first trimester.

Placenta positions

The position of your placenta is dependent on where it actually implants on your uterine wall. Some placentas attach to the front of the uterus, some to the back, and some other places. 

And while most (but not all) placenta positions are normal and don’t pose any kind of danger to you or your baby, it is very important to be familiar with the location of your placenta.

I’m going to break down all the different positions for you and dive into a bit more detail of each below.

Anterior placenta

An anterior placenta is when your placenta is attached to the front wall of your uterus. And while this is a completely normal place for your placenta to implant and develop, it might make some things just a tad trickier. 

You can think of an anterior placenta as a cushion that blocks some of your baby’s movements. This is the reason I say that it can make things a bit trickier, especially when it comes to kick counts and monitoring fetal movement.

If you have an anterior placenta and are trying to monitor your baby’s movement, I recommend focusing on your sides and lower down on your belly. These spots are where you will likely feel those first and more consistent movements.

And keep in mind, having an anterior placenta is never a reason to dismiss reduced fetal movement. If anything feels off with your baby’s movements, anterior placenta or not, always, always call your OB provider or go in for evaluation promptly!

Related Reading: Stillbirth Prevention: Actionable Things You Can Do to Reduce the Risk of Stillbirth

Benefits of anterior placenta

Having an anterior placenta doesn’t give you any added benefits over other placenta positions. It will still feed, grow, and nourish your baby just like any other placenta would.  

Anterior placenta belly shape

The placenta is relatively thin, so the location of your placenta shouldn’t impact the shape of your belly during pregnancy.

New call-to-action

Posterior placenta

Your placenta would be considered posterior if it implants in the back of your uterus. Again, this isn’t a bad (or good) thing, just another place that it might attach inside your body. 

Just as having an anterior placenta shouldn’t impact your mode of delivery, neither should a posterior placenta. As long as your placenta isn’t too close to your cervical opening, the location of it shouldn’t interfere with your ability to attempt a vaginal birth.

Fundal placenta

Your uterus, shaped like an upside down pear, is actually made up of several sections. The lowest part of your uterus, known as your cervix, opens to your vagina. Your fundus is the uppermost and widest part of your uterus and connects to your fallopian tubes.

A fundal placenta simply occurs when your placenta attaches to the top region of your uterus. This is totally normal and also shouldn’t mean anything out of the ordinary for you when it comes to your pregnancy and delivery.

Lateral placenta

Lateral is another place that your placenta might implant and grow. This means that your placenta attaches to the left or right side of your uterine wall. This is one of the less common positions for your placenta.

Are you seeing a theme here? Basically, your placenta can implant on any surface of your uterus! So far, the ones we have discussed up until this point, shouldn’t impact your pregnancy or delivery (with the exception of monitoring fetal movement with an anterior placenta). 

Low lying placenta

Now we’re going to get into the more problematic placenta positions. Only joking, I would never call your placenta problematic, but there are some placenta positions that might make attempting a vaginal birth unsafe for both you and your baby.

A low lying placenta occurs when your placenta is lying low enough that it’s within a certain, close distance to your cervix. A low lying placenta is just far enough away from your cervix to not be touching or covering it.

If found earlier in pregnancy, there is a good chance your placenta will move away from your cervix as your uterus expands. Whether or not it is safe for you to attempt a vaginal birth depends on how far your placenta is from your cervical opening at the time of delivery.

You can expect your provider to closely monitor your placenta position throughout your pregnancy, at least until it’s far enough away from your cervix to no longer be concerned.

Placenta previa

A placenta previa is when your placenta is covering your cervical opening. A vaginal birth is not a safe mode of delivery if you have a placenta previa, as it can be dangerous for your uterus to contract with your placenta that close to your cervix. 

Placenta previas are graded based on how close they are to your cervix. There are 4 different ways to describe placenta previas:

1. Partial previa

A partial previa is, well, exactly what it sounds like – your placenta is partially covering your cervix. There is a good chance that a partial previa will move away from your cervix as your pregnancy progresses.

And since it’s only partially covering the cervix, a partial previa comes with less potential complications than a complete previa.

2. Complete previa

With a complete previa, the placenta completely covers the cervix. In this case, there’s much less of a chance that the placenta will shift away from the cervix. If you find yourself in this scenario, the safest way for you to deliver your baby will be via C-section.

And of course, should you experience any amount of bleeding in pregnancy, especially with a complete known previa, you should immediately get evaluated.

3. Marginal previa

With a marginal placenta previa, the placenta is touching the cervix but not covering it. The difference between a marginal previa and a low lying placenta is the distance the placenta is from the cervix.

A low lying placenta means that the placenta is close to, but not touching, the cervix, whereas in a marginal previa, it is touching but not covering the cervix.

There is still a chance, especially if discovered earlier on in pregnancy, that a marginal previa could move and make attempting a vaginal birth safe. 

4. Low lying placenta

Reference the section above for more information about low lying placentas!

Circumvallate placenta

A circumvallate placenta has less to do with the location of the placenta and is more about the shape. With a circumvallate placenta, the fetal side of the placenta is small, causing abnormalities that can impede the amount of oxygen and nutrients your baby receives. 

Before I go any further, let me say that circumvallate placentas are rare! It can be somewhat difficult to detect during pregnancy, so often it’s not diagnosed until after delivery when the placenta is examined.

One thing of concern with a circumvallate placenta is a possible reduction in blood flow and nutrients to baby. If baby isn’t getting adequate blood flow and nutrients then it’s very possible they will experience growth restriction during the pregnancy. 

Related Reading: Everything You Ever Wanted to Know About the Placenta and Umbilical Cord

Does the placenta move during pregnancy?

Does the placenta move during pregnancy? The answer to this is yes and no. Have I confused you? Let me explain!

Once the placenta implants in the uterus it doesn’t detach and then reattach. In fact, if the placenta begins to pull away from the uterus, it can turn into an emergency. This situation is known as a placental abruption.

But I said the placenta can move during pregnancy too, didn’t I? As your pregnancy progresses, your uterus expands to accommodate your growing baby. 

As your uterus expands, your placenta moves with it. This movement is more just the embedded placenta shifting along the uterine wall than it is completely relocating.

Hopefully that’s more clear now!

How to tell where the placenta is on ultrasound

The person performing your ultrasound, whether it’s a sonographer or your OB provider, should be trained in reading and interpreting ultrasounds.

I wish I had some magical advice to offer you on interpreting ultrasounds, but I’m going to recommend leaving it to the experts. But feel free to ask your provider to point it during one of your ultrasounds if you are curious!

Wrapping up

Did you learn everything you ever wanted to know about placentas?! I did my best to take a deep dive without nerding out and boring you too much! 

I have a lot more pregnancy and birth resources for you to check out. I’ve included a few below to get you going:

Baby Registry Guide
Liesel Teen, RN-BSN

Liesel Teen

BSN, RN, Practicing Labor and Delivery Nurse

As a labor and delivery nurse, I’ve spent countless hours with women who felt anxious — even fearful — about giving birth. I want you to know it doesn’t have to be that way for you!

Are you ready to have an even better birth?

Everything in your hospital’s childbirth class – plus so. much. more. Get the knowledge and tools necessary for a positive birth experience – no matter how you deliver!

Natural Birth Class

Eliminate the what-ifs and feel strong and ready for your unmedicated birth.

Start here if birthing without an epidural is your goal!

Epidural Birth Class

Let go of fear and feel fully prepared for (and unafraid of!) your epidural birth.

Start here if you know you want that epidural – or you’re not sure what your birth goals are!

C-Section Birth Class

Release anxiety and gain a sense of control for your C-section birth.

Start here if you have a planned C-section on the horizon. You deserve birth education too!